Yaskawa Z1000 AC Drive HVAC - Manual (Page 198)

5.4 Fault Detection
u Fault Displays, Causes, and Possible Solutions
Faults are detected for drive protection, and cause the drive to stop while triggering the fault output terminal MA-MB-MC.
Remove the cause of the fault and manually clear the fault before attempting to run the drive again.
TERMS TERMS
Digital Operator: Hand Off Auto (HOA) Keypad JVOP-183
Table 5.10 Detailed Fault Displays, Causes, and Possible Solutions
Digital Operator Display Fault Name
bAT bAT Digital Operator Battery Voltage Low
Cause Possible Solution
The digital operator battery is low Replace the digital operator battery.
Digital Operator Display Fault Name
boL
Braking Transistor Overload Fault
The braking transistor reached its overload level.
Cause Possible Solution
The wrong braking resistor is installed Select the correct braking resistor.
Digital Operator Display Fault Name
bUS
Option Communication Error
• The connection was lost after establishing initial communication.
• Only detected when the run command frequency reference is assigned to an option card.
Cause Possible Solution
No signal was received from the PLC • Check for faulty wiring.
• Correct the wiring.
• Check for disconnected cables and short circuits and repair as needed.
Faulty communications wiring or an existing
short circuit
Communication data error occurred due to
noise
• Check the various options available to minimize the effects of noise.
• Counteract noise in the control circuit, main circuit, and ground wiring.
• Ensure that other equipment such as switches or relays do not cause noise. Use surge absorbers if
necessary.
• Use only recommended cables or other shielded line. Ground the shield on the controller side or the
drive input power side.
• Separate all communication wiring from drive power lines. Install an EMC noise filter to the drive
power supply input.
The option card is damaged Replace the option card if there are no problems with the wiring and the error continues to occur.
The option card is not properly connected to
the drive
• The connector pins on the option card do not line up properly with the connector pins on the drive.
• Reinstall the option card.
Digital Operator Display Fault Name
CE
MEMOBUS/Modbus Communication Error
Control data was not received for the CE detection time set to H5-09.
Cause Possible Solution
Faulty communications wiring or an existing
short circuit
• Check for faulty wiring.
• Correct the wiring.
• Check for disconnected cables and short circuits and repair as needed.
Communication data error occurred due to
noise
• Check the various options available to minimize the effects of noise.
• Counteract noise in the control circuit, main circuit, and ground wiring.
• Use only recommended cables or other shielded line. Ground the shield on the controller side or the
drive input power side.
• Ensure that other equipment such as switches or relays do not cause noise. Use surge suppressors if
required.
• Separate all communication wiring from drive power lines. Install an EMC noise filter to the drive
power supply input.
5.4 Fault Detection
198 YASKAWA ELECTRIC TOEP YAIZ1U 03A YASKAWA AC Drive – Z1000 User Manual